This invention relates to a lift assembly for use in conjunction with a vehicle. More particularly, the lift assembly is adapted to be used by a person confined to a wheel chair, whereby he may lower or raise himself between the ground and the doorway of the vehicle.
A lift assembly of this type is usually mounted in a rear or side doorway of a vehicle, such as a bus or a van. It commonly comprises a platform which can be positioned exteriorally of the vehicle and level with the vehicle floor. The user wheels himself from the interior of the vehicle out onto the platform and then actuates means which lower the platform to the ground. The reverse sequence is followed to enable the user to re-enter the vehicle.
In the design of these systems, a number of characteristics are sought to be attained. For example, it is desirable to have as compact an assembly as possible. This permits the maximum number of passengers to be carried in the vehicle -- an important feature, as many of these assemblies are used with institutional vehicles or buses. The prior art assemblies are bulky, as they use hydraulic cylinders to raise and lower the platform. The hydraulic cylinders require the provision of an anchoring super structure within the vehicle, and hydraulic reservoirs, pumps and the like.
It is therefore one object of this invention to provide a lift assembly which is compact when stored and which uses up relatively little of the interior space of the vehicle.
Another desirable objective for a system of this type is to automate it to a point where it can be used by the handicapped person without assistance from others. The commercially available assemblies of which I am aware all require the assistance of a non-handicapped person to perform one or more functions, such as opening the doors, folding away components, or the like.
It is therefore another object of the invention to provide a lift assembly which is completely mechanized and electrically sequenced so that all the movements of the doors and platform are carried out mechanically under the control of the handicapped person.
Another desirable characteristic of a system of this type is that it be constructed of components which are simple to repair and are off-the-shelf items, commonly available even in small towns. This quality is lacking to some extent in the prior art devices. It is therefore another object of the invention to provide an assembly constructed with this desirable quality in mind.
The prior art assemblies are relatively difficult to install and involve making a substantial number of bolt holes in the vehicle. Since these holes are undesirable when the owner goes to sell or trade in the vehicle, it is therefore another object of the invention to provide an assembly which can easily be installed with relatively few bolts.
Finally, it is self-evident that the assembly should operate in as safe a manner as possible. It is therefore another object to provide an assembly designed with the safety of the user in mind.